I'm having a similar problem, but mine tells me "Connection failed" after entering my code. Tinkering with the firewall doesn't seem to help, and no other program has a problem, so I'm pretty sure it's the activation wizard.

Guys what can I do when I Login into Multiplayer, as soon as I press enter it says "Your CD Key is already in use with this account". No idea what to do, just wanted to play on my account once again. Will I have to start a new account, or what should I do. Been trying to figure this out for about 2 months.